2013년 12월 29일 일요일

2_1_autocommit_vs_transaction

http://dev.mysql.com/doc/refman/5.0/en/commit.htmlBy default, MySQL runs with autocommit mode enabled. This means that as soon as you execute a statement that updates (modifies) a table, MySQL stores the update on disk to make it permanent.

To disable autocommit mode implicitly for a single series of statements, use the START TRANSACTION statement:

START TRANSACTION;SELECT @A:=SUM(salary) FROM table1 WHERE type=1;UPDATE table2 SET summary=@A WHERE type=1;COMMIT;